Japanese Patent No. 4734756 (Patent Document 1) describes a structure in which four fixing portions are provided at four corners of a weight and the weight and each of the four fixing portions are connected via support beams.
Japanese Patent No. 5037690 (Patent Document 2) describes technology of inhibiting degradation in measurement accuracy due to fluctuations of detection sensitivity of an inertial sensor by inhibiting fluctuations of natural frequency of the inertial sensor due to stress. Specifically, in a spring system in which a movable portion and a plurality of beams connected thereto are combined, an increase of a spring constant due to tensile stress acting on one beam and a decrease of a spring constant due to compressive stress acting on another beam are cancelled out each other.
Non-Patent Document 1 describes a structure of an inertial sensor in which an open-ended mass body is supported at three points, with symmetrical-type support beams being provided at two points at an open end and with the mass body being connected on a center axis at the remaining one point.